Forslag til algoritme

Her er 3 O(n) operationer, der gør det ønskede.

import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.util.Arrays;

public class FileSorter {
   
    public FileSorter(File file) {
        File[] files = file.listFiles();
        long[] fileLengths = new long[files.length];
       
        for( int i = 0; i < files.length; i++ ) {
            fileLengths[i] = files[i].length();
        }
       
        Arrays.sort(fileLengths);
       
        for( int i = fileLengths.length-1; i >= 0; i-- ) {
            System.out.println (fileLengths[i]);
        }
    }
}
class Go {
    public static void main(String[] args) {
      new FileSorter(new File("C:/"));
  }
}

Takker!

Øhm, hvis arrays.sort kører i tid O(n) tror jeg nok det er verdensrekord :)

Her er citat fra java api'en, som mere realistisk angiver O(n*log n) som udførselstid.

sort
public static void sort(long[] a)Sorts the specified array of longs into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance.

Parameters:
a - the array to be sorted.

:-)